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* 18K gold

18K White Gold (nickel-based): what it's made of, its purity, and its value

Traditional white gold formulation. Whiter than palladium variant. Nickel can trigger contact allergy — regulated in EU under REACH. Banned in some markets.

Published May 30, 2026

Quick facts

Karat
18K
Purity
75.0%
Fineness
750/1000
Color
White
Density
14.7 g/cm³
Melting point
940 °C

What it's made of

Gold
75%
Copper
10%
Nickel
10%
Zinc
5%

The gold content is fixed at 75.0% — that's what makes it 18K. The remaining metals are what set the color: Nickel and palladium are the bleaching metals — they cancel gold's yellow to give a white tone.

About 18K White Gold (nickel-based)

Traditional white gold formulation. Whiter than palladium variant. Nickel can trigger contact allergy — regulated in EU under REACH. Banned in some markets.

How much it's worth

The melt value of a 18K White Gold (nickel-based) piece is gold spot price × 0.750 × weight (g), because only 75.0% of the metal is gold. A buyer then deducts roughly 5–15% for refining and margin, so a cash offer lands just under that figure. Higher-karat gold packs in more gold per gram, so it carries a higher melt value — but it's also softer and scratches more easily, which is why everyday jewelry often uses lower karats.

* Frequently asked

FAQ

Q. How much gold is in 18K White Gold (nickel-based)?
A. 75.0% by weight. 18K means 18 parts gold out of 24, which works out to 750/1000 fineness — the rest is alloy metals added for color and durability.
Q. Is 18K White Gold (nickel-based) real gold?
A. Yes. 18K is genuine gold — it's 75.0% pure gold by weight, alloyed with other metals. It is not gold-plated or gold-filled; the gold runs all the way through.
Q. Why is 18K White Gold (nickel-based) white?
A. The color comes from the metals mixed with the gold. Nickel and palladium are the bleaching metals — they cancel gold's yellow to give a white tone.
Q. Will 18K White Gold (nickel-based) tarnish or cause skin reactions?
A. Solid gold itself doesn't tarnish, but this is a nickel-bearing white gold, and nickel can trigger contact allergy in sensitive wearers (it's regulated in the EU under REACH). Rhodium plating and palladium-based alternatives avoid the issue.

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